Line commutated current source converter based HVDC (LCC HVDC) systems are being applied to transfer power from remote wind resources to interconnect to existing ac transmission systems. The rectifier terminals of these systems are connected to weak ac systems. HVDC system design engineers have extensive experience implementing dynamic reactive compensation solutions when the inverter end of the system is weak, but the guidelines used overstate the reactive compensation needed for rectifier operation. A modified CIGRE HVDC benchmark model in PSCAD/EMTDC program is used to perform this study the impact of varying amounts of dynamic reactive compensation for rectifier operation. Simulation results will also compare the effectiveness of synchronous condensers versus static synchronous compensators (STATCOMs) in reducing incidents of commutation failures at the rectifier bus of the LCC HVDC transmission system
د. براين جونسون, د. هيس هرب, , (12-2014)

Abstract This work presents correlations between experimentally generated magnetic field strengths and computationally modeled field strengths. The experimental set-up comprised a C-shape structure designed to generate strong magnetic field strengths. The sections of the C-structure were individual solenoids made from copper-wound low carbon steel. These sections were connected such that the overall structure formed a continuous conduit for the magnetic flux and concentrated the magnetic field into an air gap. This experimental set-up could be used for magnetic annealing, or alternatively to measure the magnetostrictive strain properties of suitable materials, placed in the air gap. Magnetic field strengths of approximately 1.0 Tesla (T) were measured using a magnetic field strength meter. Finite Element Method Magnetics (FEMM) computational modeling software was used to model the design and predict field strengths. Modeled field strengths fell short of practical measurements. The efficiency of the apparatus in producing high fields is reduced due to effects related to drilling and machining of the steel core. Other reasons for discrepancies include the configuration of the C-shape, the properties of the core material, and skin effects. By building these considerations into the FEMM model, a more accurate representation of the workings of the C-shape set-up was achieved.
, , , , (1-2016)

Abstract- investigation of the use of continues wavelet transform (CWT) method to late time response analysis for detecting on body concealed threat objects proposed in this paper. The transient backscattered mechanisms of on body concealed weapons target signatures are studied using the wavelet analysis technique in which signal processing algorithm is developed and the Morlet wavelet applied to extract and analyses the re-radiated transient response of concealed targets. Experimental work was done by using simple and complex objects such as wire and handgun, Wavelet analyses of backscattered data from various objects are presented, the results show that the Continues wavelet transform (CWT) has the ability to detect and discriminate between the hidden-on body objects.
, (7-2019)